FR3116867A1 - Device and method for pumping products with low vacuum evaporation. - Google Patents

Abstract

- Device and method for pumping products with low vacuum evaporation.- The device for pumping products from a pumping zone (2) to an enclosure (3) comprises two tanks, a transfer system (8) which generates a suction of the products from the pumping zone (2) to the tanks (4A, 4B) and a transfer of the non-gaseous products from the tanks (4A, 4B) to the enclosure (3), valves (3A, 3B, 3D, 3D, 3I, 4C, 4D, 4I, 4J) to alternately either allow or block communication from one tank (4A, 4B) to the pumping zone (2) and communication from the other tank ( 4A, 4B) to the enclosure (3), and a control system (25). The transfer system (8) comprises a suction unit (13) provided with hydro-ejectors (13A, 13B) connected to each tank (4A, 4B) and generating the suction of the products and a transfer unit (20 ) provided with a pump connected to the tanks (4A, 4B) to transfer non-gaseous products to the enclosure (3). Figure for the abstract: Fig.1

Description

Device and method for pumping products with low vacuum evaporation.

The present invention relates to a device and a method for pumping products with low vacuum evaporation, from a pumping zone to a storage enclosure.

In particular, the invention relates to a device and a method for pumping products such as hydrocarbons, acids, bases, sewage sludge, biological sludge, primary sludge, and in general any product likely to generate an explosive atmosphere and/or emit volatile organic compounds into the atmosphere during pumping.

STATE OF THE ART

Many industries, for example chemical, petrochemical, agri-food, metallurgical, etc., generate sludge likely to produce explosive atmospheres and/or emit polluting volatile compounds. It is therefore necessary to pump this sludge regularly in order to be able to transport it to specialized treatment and/or storage sites.

Such pumping operations are also necessary in particular for purging industrial sewers, recovering waste produced by high-pressure water cleaning of industrial installations, extracting sludge from treatment plants, for drying tank bottoms so as to allow their inspection or maintenance, etc.

These pumping operations present many risks for the safety and health of operators and local residents and for the protection of facilities and the environment, which are linked to the explosive nature of the pumped products and the emission of harmful gases such as volatile organic compounds. For example, pumping 4 cubic meters of 98 unleaded gasoline can release 114 liters of fuel in gaseous form, which is equivalent to 210 cubic meters of toxic gas into the atmosphere.

Since volatile organic compounds are heavier than air, they may form dangerous gas pockets near the pumping operation.

In addition, the industrial cleaning activity also requires the pumping means to be completely purged and degassed due to the diversity of the products treated, the combination of which could generate a dangerous chemical reaction.

To carry out such liquid or pasty waste pumping operations, it is common to use a vacuum pump to empty a tank containing the products to be pumped into a vacuum tank. This technique allows both the pumping of layers of products (no strainer) and avoids the passage of dangerous products in the body of a rotating machine. On the other hand, it can promote the evaporation of volatile waste by lowering the boiling point, the transfer of the products to be pumped being carried out either by a depression exerted on the products or by aeraulic mode where the admitted air speed induces the movement . To do this, a suction pipe is permanently immersed in the product to be pumped. This technique has the advantage of allowing the vacuum pump to be stopped during the pumping operation by maintaining a suction capacity as long as the differential with respect to atmospheric pressure exists. This technique therefore makes it possible to completely empty the tank to be emptied. In addition, it allows the pump to be installed at great distances from the product, to avoid contact between the product and the pump, except for vapors and gases, and to limit the quantity of pollutants released.

However, this type of technique has two major drawbacks. On the one hand, pumping in industrial cleaning is most often carried out on tank bottoms which only very rarely allow the suction pipe to be fully immersed. This consequence causes air inlets at the suction which, if these were not compensated for in the case of volumetric pumps, would stop pumping. On the other hand, it promotes the boiling of products pumped under vacuum at low temperature, resulting in the release of gases and volatile products into the atmosphere, thereby increasing the environmental and explosion risks.

Moreover, during the pumping of 4 cubic meters of super 98 gasoline by known pumping methods, the first liters of gasoline that enter the large capacity vacuum tank are subjected to vacuum all the time of the pumping, with the consequence an acceleration of the evaporation of the pumped gasoline.

Among the known pumping devices, some use two-phase separators to promote the degassing of the products pumped into the tank so as to reduce the emission of volatile organic compounds. However, the internal arrangement of this type of device in a storage enclosure does not allow it to be filled, which generates a loss of volume of approximately 10% to 15%.

Document FR1 559 570 of the applicant discloses a device for pumping a product by vacuum suction, intended to at least partially overcome this problem. This pumping device comprises a vacuum source, a product suction nozzle, a pressure source, two transit tanks for product, and a set of controlled valves, connecting simultaneously and alternately, one of the transit tanks to the vacuum source and to the suction nozzle and the other of the transit tanks to the pressure source and to a product reception tank.

The vacuum suction and the pressurization of the transit tanks are preferably carried out by a single vacuum pump. The vacuum source and the pressure source being respectively constituted by the suction port and by the discharge port of the vacuum pump. Thus, the two transit tanks work alternately, which makes it possible to limit the time of exposure to the vacuum of the pumped products, so as to limit the physical phenomenon of desorption of the gases from the products.

However, the solution of document FR1 559 570 is not completely satisfactory. In particular, the use of a single vacuum pump for suction and delivery can limit the suction capacity and increase the time required for liquids to be placed under vacuum in the transit tanks, with the consequence of a possible increase in the release of volatile products. .

The object of the present invention is to remedy at least this drawback. It relates to a device for pumping products from a pumping zone to a storage enclosure, said pumping device comprising:
- two transit tanks configured to receive the products to be pumped separating into non-gaseous products and gaseous products, each of said transit tanks being provided with a product inlet, a non-gaseous product drain outlet and a suction port;
- A transfer system configured to generate a suction of the products from the pumping zone to said transit tanks and to generate a transfer of non-gaseous products from said transit tanks to the storage enclosure;
- a plurality of valves capable of being controlled and configured to alternately either allow or block communication from one of said transit tanks with the transfer system and the pumping zone and communication from the other of said transfer tanks transit with the transfer system to the storage enclosure; And
- A control system for said plurality of valves.

According to the invention, said transfer system comprises:
- a suction unit provided with at least two hydro-ejectors connected to the suction port of each of said transit tanks and configured to at least generate the suction and the separation of the products to be pumped into gaseous products and not gaseous; And
- A transfer unit provided with a volumetric transfer pump connected to the drain outlet of each of said transit tanks and configured to at least generate the transfer of non-gaseous products to the storage enclosure.

Thus, thanks to the invention, the product pumping time, during which the gas desorption phenomena take place, is minimized due to the small volume of the products pumped under vacuum. Indeed, there is no accumulation of time that the pumped products spend under vacuum.

In particular, when the products to be pumped are small volumes, the suction of the products to be pumped may be interrupted. The suction unit allows the pumping to be reprimed quickly and, simultaneously, the transfer unit allows the degassed products to be pushed back into the storage enclosure.

In addition, the transfer of non-gaseous products is obtained by a volumetric pump which limits the exposure time of the products to vacuum and therefore the desorption of gases in the storage enclosure and allows filling from the bottom of the enclosure. storage without bi-phase separator.

Advantageously, the diameter of each of said transit tanks is between 70 centimeters and 80 centimeters.

Furthermore, advantageously, the ratio between the volume and the upper surface of the transit tanks in contact with the products is between 1/30 and 1/25.

Thus, by considering transit tanks of reduced dimensions, the vacuum surface is reduced, which limits the formation of gases resulting from thermal desorption phenomena.

According to a preferred embodiment, the maximum vacuum duration of the products pumped into the transit tanks is less than or equal to 12 seconds.

Furthermore, advantageously, the suction unit is provided with a high pressure pump supplying said at least two hydro-ejectors with high-pressure water, each of said at least two hydro-ejectors discharging water into at least a water tank which feeds said high pressure pump.

Thus, the suction unit works on a water recycling principle.

Advantageously, one of said at least two hydro-ejectors is configured to compensate for suction variations over time.

In addition, advantageously, the pumping device comprises a network for rejecting the gases produced during pumping towards a rejection zone, the rejecting network comprising:
- at least one gas discharge pipe produced by said transit tanks and connecting the suction port of each of said transit tanks to said at least two hydro-ejectors, said at least one pipe also contributing to the vacuum by suction from each of said transit tanks;
- at least one water transfer pipe connecting said at least two hydro-ejectors to at least one water tank; And
- a pipe leaving said at least one water tank so as to disperse the gases produced by said transit tanks in the discharge zone.

Preferably, the discharge network also comprises a first discharge conduit for the gases produced by desorption in the storage enclosure, connecting the storage enclosure to said at least one water tank.

According to a particular embodiment, the suction unit is configured to generate a vacuum in the storage enclosure, to assist in the direct pumping of products comprising solid elements via a rear pipe. According to this particular embodiment, the discharge network also comprises a second conduit for the rejection of gases produced by desorption in the storage enclosure connecting said storage enclosure to said at least two hydro-ejectors, said second conduit also contributing to the under vacuum of the storage enclosure.

Furthermore, according to a particular embodiment, the pumping device comprises a cyclo-filter configured to filter the gases from each of said transit tanks, said cyclo-filter being arranged between said at least two hydro-ejectors and each of said tanks of transit.

In addition, the cyclo-filter is also configured to filter the gases from the storage enclosure, said cyclo-filter being arranged between said at least two hydro-ejectors and said storage enclosure.

According to a particular embodiment, the transfer unit is also configured to transfer said non-gaseous products from the storage enclosure to a another storage area.

The transfer unit is thus used both for filling and emptying the storage enclosure. The transfer unit can also pump liquid or pasty products from one tank and deliver non-gaseous products to another storage area.

In addition, advantageously, the filling level of each of said transit tanks is detected by radar sensors.

The present invention also relates to a method for pumping products from a pumping zone to a storage enclosure.

According to the invention, said product pumping method comprises the following steps, implemented alternately:
- a first valve control step consisting in allowing the suction of products from the pumping zone towards a first transit tank previously placed under vacuum by a suction unit and the separation of the pumped products into non-gaseous products and into products gas in said first transit tank and, simultaneously, to allow the transfer of non-gaseous products by a transfer unit from the second transit tank to the storage enclosure; And
- a second valve control step consisting in allowing the suction of products from the pumping zone towards the second transit tank previously placed under vacuum by the suction unit and the separation of the pumped products into non-gaseous products and gaseous products in said second transit tank and, simultaneously, to allow the transfer of non-gaseous products by the transfer unit from the first transit tank to the storage enclosure.

Advantageously, said pumping method also comprises a gas rejection step, implemented simultaneously with the implementation of the first and second valve control steps, this gas rejection step consisting in rejecting the gases produced during the separation of the products in each of said transit tanks towards a rejection zone via a rejection network.

Furthermore, according to a particular embodiment, said pumping method comprises a vacuum step consisting in generating, with the aid of the suction unit, a direct vacuum in the storage enclosure, to promote the pumping of products comprising solid elements into the storage enclosure.

In addition, said pumping method further comprises a step of transferring non-gaseous products from the storage enclosure to another storage area by the transfer unit.

The present invention also relates to:
- a unit for pumping and storing products from a pumping zone, which comprises a device for pumping products, such as that described above, as well as a storage enclosure; And
- A hydrocureur which is provided with such a pumping and storage unit.

BRIEF DESCRIPTION OF FIGURES

The appended figures will make it clear how the invention can be implemented. In these figures, identical references designate similar elements.

There is a schematic view of a particular embodiment of a pumping device in a first phase of operation.

There is a schematic view of the pumping device of the in a second phase of operation.

There is a side view of a sewer cleaner, provided in particular with a pumping device and a storage enclosure (or tank).

DETAILED DESCRIPTION

The device for pumping products (hereinafter “pump device 1”) making it possible to illustrate the invention and represented schematically in FIGS. 1 and 2, is a device intended to pump products such as sludge, solvents, oil slicks, etc., from a pumping zone 2 to a storage enclosure 3.

In the context of the present invention, it is meant:
- by "pumping zone", a place, for example a particular location, in particular on an industrial site or a tank or other container, where the products that must be pumped are located, for example to be moved to a treatment site specialized; And
- by "storage chamber", a container such as a tank, a tank, a cistern, etc., intended to receive the pumped products. This container can for example be mounted on a vehicle, as specified below in a particular application, to transport the stored products to a processing site.

As shown in Figures 1 and 2, the pumping device 1 comprises two transit tanks 4A and 4B. These transit tanks 4A and 4B are preferably cyclonic or hydrocyclone tanks. Each of these transit tanks 4A and 4B is intended to contain products to be pumped. The transit tanks 4A and 4B are configured to reduce the vacuum exposure time of the pumped product in order to minimize the risk of physical transformation of the pumped products into gas.

Each of the transit tanks 4A and 4B is provided with a product inlet 5A, 5B to receive the products, a drain outlet 7A, 7B to discharge the non-gaseous products resulting from the separation into different phases of the products pumped towards a storage enclosure 3 and a suction port 6A, 6B for vacuuming or venting.

According to a preferred embodiment,each of the transit tanks 4A, 4B has a diameter between 70 centimeters and 80 centimeters. Furthermore, each of the transit tanks 4A, 4B has a reduced capacity, preferably between 100 to 150 liters. In addition, the ratio between the volume and the surface of the transit tanks 4A and 4B in contact with the pumped products is comprised, preferably, in a ratio between 1/30 and 1/25. The desorption phenomena in the transit tanks 4A and 4B are related to their dimensions and to the vacuum surface of the products pumped in the transit tanks 4A and 4B. At least these two parameters make it possible to reduce the exposure to vacuum of the pumped products in time and at the surface and to separate in the transit tanks 4A and 4B the gaseous products generated by the vacuuming in aeraulic mode of the non-gaseous products. This leads to a reduction in the quantity of polluting gases. By way of example, the pumping of 4 cubic meters of unleaded gasoline 98 by the pumping device 1 generates fourteen liters of fuel in gaseous form, instead of 114 liters in the known devices, which means a reduction in the emission of toxic gases into the atmosphere by more than eight times.

Thus, the vacuum exposure time of the pumped products is lowered, for example for 4 cubic meters, by 240 seconds in the event of direct pumping by the storage enclosure 3 to 12 seconds by the transit tanks 4A and 4B, this which corresponds to a twenty-fold reduction in vacuuming time compared to conventional pumping means. Moreover, in the case of direct pumping by the storage enclosure 3, the more the volume of the pumped products increases, the greater the time of exposure to the vacuum of the products and therefore the production of gas by desorption. On the contrary, in the case of the pumping device 1 with transit tanks 4A and 4B, the vacuum exposure time of the pumped products does not depend on the volume of pumped products and remains constant.

In a particular embodiment, 4K radar sensors can be provided to detect the filling level of the tanks 4A and 4B. These 4K radar sensors are more efficient than mechanical means. In addition, each of the transit tanks 4A, 4B can be fitted with 4Z floating balls to block any leakage of products through the suction orifice 6A, 6B.

The pumping device 1 further comprises a transfer system 8,which can generate a suction of the products from the pumping zone 2 towards the transit tanks 4A and 4B and generate a discharge of the non-gaseous pumped products following the phenomena of thermal desorption in the transit tanks 4A and 4B to storage enclosure 3.

According to the invention, this transfer system 8 is formed by a suction unit 13 and a transfer unit 20. As represented in FIGS. 1 and 2, the suction unit 13 and the transfer unit Transfer 20 are two separate units.

The suction unit 13 generates suction of the products from the pumping zone 2 by placing the transit tanks 4A and 4B under vacuum. It is connected to the suction ports 6A and 6B of the transit tanks 4A and 4B. The products sucked from the pumping zone 2 to each of the transit tanks 4A, 4B circulate through product transfer pipes 9A and 9B which connect the pumping zone 2 (via for example a common pipe) to the product inlets 5A and 5B transit tanks 4A and 4B.

More particularly, the suction unit 13 (also called the vacuum unit) comprises at least two hydro-ejectors 13A and 13B. The hydro-ejectors 13A and 13B are connected to a high-pressure pump 14 , which supplies them with high-pressure water via a pipe 14A on which valves 13C and 13D are arranged. The high-pressure pump 14 makes it possible to ensure a flow of pressure water according to demand, in each of the hydro-ejectors 13A, 13B, when the valves 13C and 13D are open.

Unlike a vacuum pump whose flow rate is fixed by its speed of rotation, the use of a high pressure pump makes it possible to modulate the flow rate of high pressure water which it injects into the hydro-ejectors 13A and 13B. A vacuum pump can see its speed vary by a factor of 1.5. For example, its speed of rotation can vary between 1000 cubic meters per hour to 1500 cubic meters per hour or between 1500 cubic meters per hour and 3000 cubic meters per hour. However, when the suction unit 13 has generated the vacuum in the transit tanks 4A and 4B in a few minutes, it is sufficient simply to compensate for the air intakes which may require, for example, 20% of the flow . Such a reduction is possible with the high pressure pump 14. This contributes to lower maintenance costs. The modulation of the water flow can also be generated by a booster pump 141 arranged upstream of the high pressure pump 14. In addition, the high pressure pump makes it possible to generate a pressure of between 500 bar and 2000 bar.

The hydro-ejectors 13A and 13B push the water supplied by the high-pressure pump 14 into a water tank 15A via the pipes 18A and 15D.This water tank 15A communicates with another water tank 15B so that the two water tanks 15A and 15B serve as water reservoirs for the high pressure pump 14. Each water tank 15A, 15B is provided a valve 27 for emptying and frost protection. Each 15A, 15B tank of water also includes a 15F bursting pot. The presence of two water tanks 15A and 15B, arranged on either side of the storage enclosure 2, results from the need to balance the pumping device 1. According to a particular embodiment, a water filter 26 is arranged between the water tanks 15A and 15B and the high pressure pump 14.Other filters, including a self-cleaning filter and a five micron bag filter, can also be arranged between the booster pump 141 and the high pressure pump 14.

Each of the hydro-injectors 13A, 13B is provided with a suction mouth 16A, 16B which is connected to the suction orifice 6A, 6B of each transit tank 4A, 4B notably via pipes 17A, 17B and 18 vacuum rejection.

Thus, the passage of water in the hydro-ejectors 13A and 13B generates, by Venturi effect, a call for air at the level of the suction mouth 16A, 16B of each hydro-ejector 13A, 13B. This call for air generated in the pipes 17A, 17B and 18 produces the evacuation of the transit tanks 4A and 4B. To create the Venturi effect, water has a good efficiency, better for example than air. In addition, the water used makes it possible to trap the gases by wetting. In addition, the use of the Venturi effect with high pressure water (about 300 bar) makes it possible to obtain a vacuum of 90%.

In a preferred embodiment, one of the hydro-ejectors 13A is used to generate the initial suction or initial vacuuming of the transit tanks 4A and B and the other hydro-ejector 13B is configured to compensate for the variations or intakes of air over time once the vacuum is generated.

Furthermore, the non-gaseous products may contain solid elements so that their pumping is done directly in the storage enclosure 3 by placing it under vacuum and by pumping through a pipe 3C located near the bottom of the tank. storage enclosure 2.

In this particular embodiment, the suction unit 13 generates suction in the storage enclosure 3 via a conduit 3G connecting the suction mouth 16A, 16B of each hydro-ejector 13A, 13B to an orifice arranged on the storage enclosure 3. This orifice is opened or closed by a valve 3D arranged on the conduit 3G.

As shown on the and 2, the transfer unit 20 generates the emptying of the non-gaseous products (resulting from the separation of the products in the transit tanks 4A and 4B) towards the storage enclosure 3. The non-gaseous products circulate in a transfer line 20A which connects the transfer outlets 7A and 7B to the storage enclosure 3. A valve 3A is arranged on the pipe 20A near a product inlet in the bottom of the storage enclosure 3.

In a preferred embodiment, the transfer unit 20 comprises a volumetric pump 20 which pumps the non-gaseous products and delivers them into the storage enclosure 3. This volumetric pump 20 is mounted on the transfer pipe 20A so that 'it is connected to the discharge outlet 7A, 7B of each of the transit tanks 4A, 4B and the inlet of non-gaseous products of the storage enclosure 3. By way of example, the volumetric pump 20 is a pump volumetric type ROOTES for fluids and pastes.

According to a particular embodiment, the direction of delivery of the volumetric pump 20 can be reversed. The volumetric pump 20 can then deliver the non-gaseous products from the storage enclosure 3 to a another storage area (not shown). We hear by " another storage area” another storage enclosure, a specialized processing and/or storage site, etc. Valves 22A and 22B can be arranged on either side of the volumetric pump 20 so as to suck in or push back the non-gaseous products depending on the direction of travel. The volumetric pump 20 has a dual function of filling and emptying the storage enclosure 3 and also offers the possibility of being used as a simple transfer pump.

In addition, the pumping device 1 also includes a gas discharge network 19, in which circulate the gases generated during the pumping of the products. This network 19 is configured to reject these gases towards a rejection zone. To do this, it comprises the pipes 17A and 17B which connect the suction port 6A, 6B of each transit tank 4A, 4B to the suction mouth 16A, 16B of each hydro-ejector 13A, 13B of the suction unit 13. Thus, the vacuuming of the transit tanks 4A, 4B participates in the rejection of the gases resulting from the separation of the pumped products into non-gaseous products and gaseous products due to the phenomena of desorption in these tanks 4A and 4B .

The network 19 also includes the water transfer pipe 18A which connects the hydro-ejectors 13A and 13B to the water tank 15A. Thus, the gas vapors entering the hydro-injectors 13 through the suction mouths 13A and 13B are trapped by wetting in the water which is pushed back into the water tanks 15A and 15B. This gas trapping provides environmental relief from potentially toxic and polluting gas releases.

As shown in Figures 1 and 2, the gas discharge network 19 also includes a pipe 15C which is mounted by one end on the upper part of the water tanks 15A and 15B and the other end 15E of which opens into the area release area so that gases trapped in the water can escape to the release area.

The gases to be rejected also result from phenomena of desorption of the products, located on the surface of the storage enclosure 3. According to a particular embodiment, the network 19 also comprises a rejection conduit 3F which connects the storage enclosure storage 3 directly to the water tank 15A.

Furthermore, in a particular embodiment in which the suction unit 13 generates suction in the storage enclosure 3, the pipe 3G connecting the suction mouth 16A, 16B of each hydro-ejector 13A, 13B to the orifice near the valve 3D contributes to the discharge of the gases resulting from the desorption in the storage enclosure 3 and is part of the discharge network 19.

As shown in Figures 1 and 2, the pumping device 1 also comprises a cyclo-filter 23 which is arranged between the hydro-ejectors 13A and 13B on one side and the transit tanks 4A and 4B and the storage enclosure 3 on the other side. The cyclo-filter 23 is also fitted with a drain valve 27 which also allows frost protection.

In this embodiment, the pipes 17A and 17B and the pipe 3G have a common part on which the cyclo-filter 23 is mounted so that the gases flowing in these pipes are filtered by the cyclo-filter 23 before entering the hydro-ejectors 13A and 13B. The filtering of the gases in the cyclo-filter 23 thus makes it possible, in particular, to eliminate gases of small particles which could pollute the suction unit 13.

Furthermore, the pumping device 1 is also provided with a plurality of valves 3A, 3B, 3D, 3E, 3I, 4C, 4D, 4I and 4J whose opening, closing and orientation are controlled by a system control 25 of the usual type, not further described in this description. The opening, closing and orientation of this plurality of valves 3A, 3B, 3D, 3E, 3I, 4C, 4D, 4I and 4J can, alternately, either allow or block the pumping of the products from the zone of pumping 2 to one of the transit tanks 4A, 4B placed under vacuum by the suction unit 13 and the discharge of the non-gaseous products from the other transit tank 4B, 4A to the storage enclosure 3 by the discharge unit 20, as specified below.

Thus, the vacuuming time is limited as much as possible:
- by using transit tanks 4A and 4B of reduced capacity;
- By filling and emptying simultaneously and alternately these transit tanks 4A and 4B; And
- Using to empty the transit tanks 4A and 4B, a transfer unit 20 which is separate from the suction unit 13 (or vacuum).

According to a preferred embodiment, valves 4C, 4D, 4I and 4J are three-way valves. The valve 4J is arranged between a pumping pipe 2A and the pipes 9A and 9B which together connect the pumping zone 2 to the product inlets 5A and 5B of the transit tanks 4A and 4B. The valve 4J can take two orientations making it possible to direct the pumping of the products towards one or the other of the transit tanks 4A and 4B. Valve 4I is arranged on line 20A between transfer pump 20 and outlet ports 7A and 7B. The valve 4I is capable of allowing the transfer of non-gaseous products into the storage enclosure 3 and coming either from the transit tank 4A or from the transit tank 4B depending on its orientation. The valves 4C and 4D are each arranged on one of the pipes 17A, 17B which connects a suction port 6A, 6B to the suction unit 13.

The control system 25 can simultaneously control the orientation of the three-way valves 4C, 4D, 4I and 4J.

In this configuration shown in the , the transit tank 4B is connected to the suction unit 13 by the pipes 17B and 18 and to the pumping zone 2 by the pipes 9B and 2A. The transit tank 4A is connected, for its part, to the transfer unit 20 by the transfer pipe 20A which leads to the storage enclosure 3.

The control system 25 can, alternately, simultaneously control the different orientations of the valves 4C and 4D and the orientation of the valve 4J for filling the transit tank 4B only and the orientation of the valve 4I for the emptying of the transit tank 4A. Each of the 4C, 4D, 4I and 4D valves includes two orientations. The first orientation of the valves 4C and 4D corresponds, respectively, to the opening of a venting of the transit tank 4A and to the opening of a communication of the transit tank 4B with the unit suction 13. The second orientation of the valves 4C and 4D corresponds, respectively, to the opening of a venting of the transit tank 4B and to the opening of a communication of the transit tank 4A with the suction unit 13. Furthermore, the first, respectively second, orientation of the valve 4I allows the opening, respectively closing, of the communication between the transit tank 4A and the storage enclosure 3 and the closing, respectively opening, of the communication between the transit tank 4B and the storage enclosure 3. The first, respectively second, orientation of the valve 4J allows the opening, respectively closing, of the communication between the pumping zone 2 and the transit tank 4B, and the closure, respectively opening, communication between transit tank 4A and storage enclosure 3.

In this configuration shown in the , the transit tank 4A is connected to the suction unit 13 by the pipes 17A and 18 and to the pumping zone 2 by the transfer pipes 2A and 9A while the transit tank 4B is connected to the pump of transfer 20 via the transfer line 20A which connects it to the storage enclosure 3.

The pumping device, as described above, implements a process for pumping products from the pumping zone 2 to the storage enclosure 3. This pumping process, which generates low vacuum evaporation of products, comprises a plurality of steps specified below.

According to a preferred embodiment, to create a vacuum, the high pressure pump 14 supplies water at high pressure to the hydro-ejectors 13A and 13B. More particularly, the high pressure pump 14 makes it possible to create a vacuum by injecting high pressure water into one of the hydro-ejectors 13A, 13B at a rate of 70 liters at 1000 bar corresponding to a power of 140 kilowatts and approximately 2500 cubic meters per hour of suction volume. With such power, the vacuum is achieved quickly. The acceleration of the water in the hydro-ejector 13A, 13B generates, by Venturi effect, a depression at the level of the suction mouths 16A and 16B. This air depression is at the origin of the vacuuming of the transit tanks 4A and 4B via the conduits 17A, 17B and 18. It can also generate a vacuuming of the storage enclosure 3 by via conduit 3G if the products to be pumped include solid elements.

When the vacuum is created, the valve 13C of the hydro-ejector 13A is closed so as to cut off the flow of water entering this hydro-ejector 13A. The valve 13D, previously closed, is then opened so that the high pressure pump 14 supplies high pressure water to the second hydro-ejector 13B. This 13B hydro-ejector uses, for example, 15 liters of water at a pressure of 1000bar only to compensate for air intakes. This reduction in flow makes it possible to pass to an absorbed power of approximately 30 kilowatts and 500 cubic meters per hour of suction flow. This phase allows significant energy savings.

In a first valve control step, the control system 25 controls:
- the opening of the valve 3I which allows communication between the suction unit 13 and the transit tanks 4A and 4B,
- the first orientation of the valves 4D and 4J so that the transit tank 4B is placed under vacuum by the suction unit 13 and fills with products from the pumping zone 2, and
- the first orientation of the valves 4C and 4I so that the transit tank 4A is exposed to the open air and the transfer unit 20 transfers the non-gaseous products to the storage enclosure 3 which is at atmospheric pressure .

Consequently, the suction generated by the suction unit 13 leads to the pumping of the products from the pumping zone 2 towards the transit tank 4B via the conduits 2A and 9B as illustrated by the arrows on the .

Simultaneously, the first orientation of the valve 4C which places the transit tank 4A in the open air prevents the aspiration of product from the pumping zone 2 into this transit tank 4A. The first orientation of the valve 4I puts the transfer outlet 7A of the transit tank 4A in communication with the volumetric pump 20 to deliver the non-gaseous products resulting from a prior separation of the pumped products, towards the storage enclosure 3 by through line 20A. The transit tank 4A then empties.

Alternately to this first valve control step, in a second step, the control system 25 controls the second orientation of the valve 4C and the second orientation of the valve 4J so that the transit tank 4A is placed under vacuum by the suction unit 13 and fills with products from the pumping zone 2. Simultaneously, the system controls the second orientation of the valve 4D and the second orientation of the valve 4I so that the transit tank 4B is venting and the transfer unit 20 transfers the non-gaseous products previously pumped into this transit tank 4B to the storage enclosure 3. The suction generated by the suction unit 13 leads to the pumping products from the pumping zone 2 to the transit tank 4A via the pipes 2A and 9A as illustrated by the arrows on the . The second orientation of the valve 4I puts the transfer outlet 7B of the transit tank 4B in communication with the volumetric pump 20 to deliver the non-gaseous products resulting from a prior separation of the pumped products, towards the storage enclosure 3 by through line 20A. The transit tank 4B then empties.

These two valve control steps are implemented alternately throughout pumping.

Thus, the two transit tanks 4A and 4B work alternately, which makes it possible to limit the time of exposure to vacuum of the pumped products so as to limit the phenomena of desorption of the gases dissolved in the products. This exposure time is a maximum of 12 seconds.

A gas rejection step is implemented during the steps described previously. During this gas discharge step, the gases generated by the separation of the products and by desorption phenomena are discharged into a discharge zone via the discharge network 19.

In the step of , simultaneously with the filling of the transit tank 4B by the products, the first orientation of the valve 4D allows the evacuation of the gases resulting from the pumping of products. These gases or non-gaseous products pass through the cyclo-filter 23 then the hydro-ejectors 13A and 13B where they are trapped by wetting in the water tanks 15A, 15B before being evacuated by the vertical pipe 15C towards the zone of rejection.

Furthermore, in the step of , simultaneously with the filling of the transit tank 4A by the products, the second orientation of the valve 4C allows the evacuation of the gases resulting from the pumping of products. These gases pass through the cyclo-filter 23 then the hydro-ejectors 13A and 13B where they are trapped by wetting in the water tanks 15A, 15B before being evacuated by the vertical pipe 15C towards the discharge zone. The flow of non-gaseous products is illustrated by the arrow on the .

During the gas rejection step, when the products are pumped directly through the storage enclosure 3, the gases produced by desorption in the storage enclosure 3 circulate in the pipes 3F and 15D as far as the tank 15A , 15B of water then are evacuated by the vertical pipe 15C.

On the other hand, when the non-gaseous products contain solid elements and the suction unit 13 has generated a vacuum in the storage enclosure 3 during the vacuum step, the solid elements are stopped by the cyclo-filter 23A via the conduit 3G.

In addition, during a discharge step (or emptying), which can be implemented later in the other steps of the process, the non-gaseous products present in the storage enclosure 3 can be pushed back from storage enclosure 3 to another area (not shown) by the transfer unit 20.

In the context of the present invention, the pumping device 1, as described, can be used for various operations or works (at high pressure).

The pumping device 1 and the storage enclosure 3 can be part of a unit 29 for pumping and storing products.

In a preferred application, the unit 29 (therefore comprising the pumping device 1 and the storage enclosure 3 is mounted on a sewer cleaner 30 represented on the . The sewer cleaner 30 comprises a carrier vehicle 31 provided with a frame 32 intended to receive equipment. The frame 32 comprises in particular, from the rear to the front, the storage enclosure 3 the transit tanks of which only the transit tank 4A is visible on the , and a casing 33 which comprises at least part of the elements of the suction unit 13 and of the discharge unit 20. The sewer cleaner 30 can be a sanitation sewer cleaner which is intended, in particular, to ensure cleaning and pumping operations for wastewater networks and sanitation works. The hydrocleaner 30 can also be an industrial hydrocleaner which is intended for cleaning work on equipment and industrial installations, and in particular for cleaning work on oil and oil-related sites.

Claims (15)

Device for pumping products from a pumping zone (2) to a storage enclosure (3), said pumping device (1) comprising:
- two transit tanks (4A, 4B) configured to receive the products to be pumped separating into non-gaseous products and gaseous products, each of said transit tanks (4A, 4B) being provided with a product inlet (5A, 5B ), a drain outlet (7A, 7B) for non-gaseous products and a suction port (6A, 6B);
- a transfer system (8) configured to generate a suction of the products from the pumping zone (2) towards the said transit tanks (4A, 4B) and to generate a transfer of the non-gaseous products from the said transit tanks (4A, 4B ) to the storage enclosure (3);
- a plurality of valves (3A, 3B, 3D, 3E, 3I, 4C, 4D, 4I, 4J) capable of being controlled and configured to alternately either allow or block communication from one of said transit tanks ( 4A, 4B) with the transfer system (8) and the pumping zone (2) and communication from the other of said transit tanks (4A, 4B) with the transfer system (8) towards the storage enclosure (3); And
- a control system (25) of said plurality of valves (3A, 3B, 3D, 3 ^E , 3I, 4C, 4D, 4I, 4J),
characterized in that said transfer system comprises:
- a suction unit (13) provided with at least two hydro-ejectors (13A, 13B) connected to the suction port (5A, 5B) of each of said transit tanks (4A, 4B) and configured to at least generating the suction and the separation of the products to be pumped into gaseous and non-gaseous products; and
- a transfer unit (20) provided with a volumetric transfer pump connected to the drain outlet (7A, 7B) of each of said transit tanks (4A, 4B) and configured to at least generate the transfer of non-gaseous products to the storage enclosure (3). Pumping device according to claim 1,
characterized in that the diameter of each of said transit tanks (4A, 4B) is between 70 centimeters and 80 centimeters. Pumping device according to one of claims 1 and 2,
characterized in that the ratio between the volume and the upper surface of the transit tanks in contact (4A, 4B) with the products is between 1/30 and 1/25. Pumping device according to any one of the preceding claims,
characterized in that the maximum vacuum duration of the products pumped into one of the transit tanks (4A, 4B) is less than or equal to 12 seconds. Pumping device according to any one of the preceding claims,
characterized in that the suction unit (13) is provided with a high pressure pump (14) supplying said at least two hydro-ejectors (13A, 13B) with water at high pressure, each of said at least two hydro- ejectors (13A, 13B) delivering water into at least one water tank (15A, 15B) which supplies said high pressure pump (14). Pumping device according to any one of the preceding claims
characterized in that it comprises a network (19) for rejecting the gases produced during pumping towards a reject zone, the reject network comprising:
- at least one pipe (17A, 17B) for rejecting the gases produced by said transit tanks (4A, 4B) and connecting the suction port (6A, 6B) of each of said transit tanks (4A, 4B) to said at least two hydro-ejectors (13A, 13B), said at least one conduit (17A, 17B) also contributing to the vacuuming by suction of each of said transit tanks (4A, 4B);
- at least one pipe (18A, 15D) for transferring water connecting said at least two hydro-ejectors to at least one water tank (15A, 15B); And
- a pipe (15) leaving said at least one water tank (15A, 15B) so as to disperse the gases produced by said transit tanks (4A, 4B) in the discharge zone. Pumping device according to any one of the preceding claims,
characterized in that the discharge network (19) also comprises a first conduit (3F) for discharging the gases produced by desorption into the storage enclosure (3), connecting the storage enclosure (3) to the said at least one water tank (15A, 15B). Pumping device according to any one of the preceding claims,
characterized in that the suction unit (13) is configured to generate a vacuum in the storage enclosure (3), to aid the direct pumping through a rear pipe of products comprising solid elements. Pumping device according to the preceding claim,
characterized in that the discharge network (19) comprises a second pipe (3G) for discharging the gases produced by desorption into the storage enclosure (3), connecting the said storage enclosure (3) to the said at least two hydro-ejectors (13), said second conduit (3G) also contributing to the vacuuming of the storage enclosure (3). Pumping device according to any one of the preceding claims,
characterized in that it comprises a cyclo-filter (23) configured to filter the gases from each of said transit tanks (4A, 4B), said cyclo-filter (23) being arranged between said at least two hydro-ejectors ( 13A, 13B) and each of said transit tanks (4A, 4B). Pumping device according to any one of the preceding claims,
characterized in that the transfer unit (20) is also configured to transfer said non-gaseous products from the storage enclosure (3) to another storage area. Unit for pumping and storing products from a pumping zone (2),
characterized in that it comprises a product pumping device (1) such as that specified under any one of claims 1 to 11, as well as a storage enclosure (3). Hydrocleaner,
characterized in that it comprises a pump and storage unit (29), such as that specified in claim 12. Method of pumping products from a pumping zone (2) to a storage enclosure (3),
characterized in that it comprises the following steps, implemented alternately:
- a first valve control step consisting in allowing the suction of products from the pumping zone (2) towards a first transit tank (4A, 4B) previously placed under vacuum by a suction unit (13) and the separation of the pumped products into non-gaseous products and gaseous products in said first transit tank (4A, 4B) and, simultaneously, to allow the transfer of the non-gaseous products by a transfer unit (20) from the second transit tank ( 4A, 4B) to the storage enclosure (3); And
- a second valve control step consisting in allowing the suction of products from the pumping zone (2) towards the second transit tank (4A, 4B) previously placed under vacuum by the suction unit (13) and the separation of the pumped products into non-gaseous products and gaseous products in said second transit tank (4A, 4B) and, simultaneously, to allow the transfer of the non-gaseous products by the transfer unit of the first transit tank (4A , 4B) to the storage enclosure (3). Pumping method according to claim 14,
characterized in that it also comprises a gas rejection step, implemented simultaneously with the implementation of the first and second valve control steps, this gas rejection step consisting in rejecting the gases produced during the separation of the products in each of said transit tanks (4A, 4B) towards a rejection zone via a rejection network (19).